The Nebraska Center for Virology (NCV), a NIH Center for Biomedical Research Excellence, proposes the continuation of its Research Training in Comparative Viral Pathogenesis program. This highly successful program is unique because it boasts research strengths in human, animal, and plant viruses, and its research experiences are comparative in nature, an emphasis not available at other institutions. This comparative orientation makes the program particularly stimulating and motivating for developing biomedical researchers equipped to lend expertise to infectious viral diseases and to apply newly acquired knowledge and skills to research, biodefense readiness, and public health and related activities. The program's long- range goal is to develop a cadre of junior scientists and investigators who are well grounded in fundamental knowledge in viral pathogenesis and laboratory research experience. The program's faculty mentors are well-funded academicians with programs that offer outstanding and highly relevant research experiences to trainees and the NCV is an established world-class research program that supports integrated, broad-based training at all levels. Specific Aims: 1) Continue to develop an interactive, productive, and exciting interdisciplinary environment where six pre-doctoral trainees and two postdoctoral fellows per year receive an outstanding education in pathogenesis and the links between viral infections and disease. 2) Support training efforts in three major emphasis areas (human, animal, and plant viruses), coalescing around comparative research experiences. 3) Provide an enriching learning environment through a variety of activities (e.g., training in research ethics and grant development, participation in a journal club, and attendance at and participation in a seminar series, symposium, and retreat). 4) Foster communication among trainees and faculty. The NCV enjoys exceptional institutional commitment and demand among program applicants has increased exponentially since the program's inception. The program's continuation is crucial to meeting the NCV's education goals. RELEVANCE (See instructions): Emerging and re-emerging viral infectious diseases such as Avian Flu, SARS, West Nile, Ebola, and the monkeypox virus, together with the ongoing AIDS epidemic, highlight a national need for basic research on causative agents to better understand pathogenesis and how viral infections cause disease. There are not enough trained researchers to meet this need, especially when diseases caused by emerging and re- emerging agents are of health and national security significance. There is an urgent national need to provide training to individuals with the potential to perform high-quality research in viral pathogenesis and equip them to be productive throughout their careers.